A number of indenoisoquinolines were prepared and evaluated for cytotoxicity in human cancer cell cultures and for activity versus topoisomerase I. The two most cytotoxic indenoisoquinolines proved to be cis-6-ethyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9(methylenedioxy)-5,11-di oxo-11H-indeno[1,2-c]isoquinoline and cis-6-allyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-d ioxo-(11H)indeno[1,2-c]isoquinoline. Two of the most potent topoisomerase I inhibitors were 6-(3-carboxy-1-propyl)-5,6-dihydro-5,11-dioxo-11H-indeno[1,2-c]isoquinolin e (26) and 6-ethyl-2,3-dimethoxy-8,9-(methylenedioxy)-11H-indeno[1,2-c]isoquinolinium chloride (27). Two additional potent topoisomerase I inhibitors, 6-allyl-5,6-dihydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-dioxo-11H-inde no[1,2-c]isoquinoline (13c) and 5,6-dihydro-6-(4-hydoxybut-1-yl)-2,3-dimethoxy-8,9-methylenedioxy-5,11 dioxo-(11H)-indeno[1,2-c]isoquinoline (19a), did not unwind DNA and did not affect topoisomerase II.

Un certo numero di indenoisoquinolines sono stati preparati e valutato stati per citotossicità nelle colture umane delle cellule di cancro e per attività contro il topoisomerase I. I due indenoisoquinolines più citotossici sono risultato essere cis-6-ethyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9(methylenedioxy)-5,11-di oxo-11H-indeno[1,2-c]isoquinoline e cis-6-allyl-5,6,12,13-tetrahydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-d ioxo-(11H)indeno[1,2-c]isoquinoline. Due degli inibitori di topoisomerase più potenti I erano 6-(3-carboxy-1-propyl)-5.6-diidro-5.11-dioxo-11H-indeno[1,2-c]isoquinolin e (26) e 6-etile-2.3-dimetossi-8.9-(methylenedioxy)-11H-indeno[1,2-c]isoquinolinium cloruro (27). Due inibitori di topoisomerase I, 6-allyl-5,6-dihydro-2,3-dimethoxy-8,9-(methylenedioxy)-5,11-dioxo-11H-inde no[1,2-c]isoquinoline (13c) e 5,6-dihydro-6-(4-hydoxybut-1-yl)-2,3-dimethoxy-8,9-methylenedioxy-5,11 potenti supplementari dioxo-(11H)-indeno[1,2-c]isoquinoline (19a), non hanno svolto il DNA e non hanno interessato il topoisomerase II.